Continuous flow folding device with storage and retrieval system for producing various sizes of folds

ABSTRACT

A PASSIVE, LIMP SHEET MATERIAL FOLDING DEVICE WHICH PASSIVELY ORIENTS AND/OR URGES THE EDGES AND ADJACENT PORTION OF THE SHEET TO A POSITION WHEREBY THE SHEET MATERIAL FOLDS ITSELF IN A NATURAL FLOW BEND PECULIAR TO THE PARTICULAR SHEET MATERIAL AS THE SHEET MATERIAL ACTIVELY PASSES THROUGH THE DEVICE. THE DEVICE IS SELF-STARTING, AND THE EDGE AND ADJACENT PORTION OF THE MOVING SHEET IS URGED TO ADVANCE ARCUATELY TOWARD THE BODY OF THE MATERIAL THEREBY FOLDING OVER ITSELF. THE DEVICE INCLUDES AN EDGE-ORIENTING RAMP ALONG WHICH THE SHEET MATERIAL EDGES RISES, A PLY SEPARATOR WHICH RESTRAINS THE BODY DURING THE ELEVATION OF THE EDGE AND SEPARATES THE FOLDED PLIES, AND A NATURAL FLOW GUIDE PLATE WHICH FOLLOWS THE CONTOUR OF THE NATURAL BEND OF THE SHEET MATERIAL DURING THE FOLDING OF THE MATERIAL. A PLURALITY OF SHEET MATERIAL FOLDING DEVICES FOR ORIENTING SHEET MATERIAL TO FOLD NATURALLY TO PRODUCE DIFFERENT SIZE HEMS ARE PREMOUNTED ON PLATES OR BASES RADIALLY EXTENDING FROM A COMMON AXIS AND ROTATIONALLY INDEXABLE AS DESIRED BY THE USER INTO A WORKLINE PROVIDING A ROTARY INDEXABLE STORAGE AND RETRIEVAL SYSTEM.

United States Patent [72] Inventor Thomas L. Flanagan Killingworth, Conn.

[21] Appl. No. 718,445

[22) Filed Apr. 3, I968 [45] Patented June 28, I971 [73] Assignee Wagner Research Corporation New York, N.Y.

{54] CONTINUOUS FLOW FOLDING DEVICE WITH STORAGE AND RETRIEVAL SYSTEM FOR PRODUCING VARIOUS SIZES OF FOLDS 4 Claims, 9 Drawing Figs.

[52] U.S. Cl 270/93,

[51] Int. Cl B6511 45/22 [50] Field of Search .t 270/40, 41,

[56] References Cited UNITED STATES PATENTS 2,430,463 I III 947 Gilbert et al 270/93 2,540,844 2/1951 Strauss 270/93 3,296,986 l/l967 Gansl 112/1 47X 3,330,553 7/1967 Couzens et al ABSTRACT: A passive, limp sheet material folding device which passively orients and/or urges the edge and adjacent portion of the sheet to a position whereby the sheet material folds itself in a natural flow bend peculiar to the particular sheet material as the sheet material actively passes through the device. The device is self-starting, and the edge and adjacent portion of the moving sheet is urged to advance arcuately toward the body of the material thereby folding over itself. The device includes an edge-orienting ramp along which the sheet material edge rises, a ply separator which restrains the body during the elevation of the edge and separates the folded plies, and a natural flow guide plate which follows the contour of the natural bend of the sheet material during the folding of the material. A plurality of sheet material folding devices for orienting'sheet material to fold naturally to produce different size hems are premounted on plates or bases radially extending from a common axis and rotationally indexable as desired by the user into a workline providing a rotary indexable storage and retrieval system.

PATENTED JUN28 197i SHEET 1 OF 5 A s; 4 .w.

INVENTOR rHoMAs L. FLA/VAGAN BY L PATENTEU JUN28 1971 SHEET 2 0F 5 FIG. 2

INVENTOR THOMAS L. FLAA/AGA/V ATENTEH JUN28|971 SHEET 4 OF 5 lNVENTOR THOMAS L. FLANAGAN ATTofiNEY CONTINUOUS FLOW FOLDING DEVICE WITH STORAGE AND RETRIEVAL SYSTEM FOR PRODUCING VARIOUS SIZES OF FOLDS The present invention relates to devices for progressively folding continuously moving or progressively flowing limp sheet material as such material passes through the folding device. In particular, the present invention is a passive sheet folding device which directs and orients the edge and adjacent portion of limp sheet material into a natural flow fold as the limp material actively passes through the folding device.

In copending application Ser. No. 676,756, filed Oct. 20, 1967, now US. Pat. No. 3,477,397, by George F. Hawley and assigned to the same assignee as the present application there is described a machine or apparatus which processes bulk limp sheet material, such as cloth or other fabriclike or clothlike material into finished flat articles, such as flat bed sheets, table cloths, bed spreads and the like. ln general, the said copending application describes apparatus which provides a storage or retaining bed for a bulk supply of limp material, such as a roll of material of predetermined width and having a length of several thousand yards. The end of the bulk supply is connected to a drawout mechanism which draws a predetermined length of the material from the bulk supply. The predetermined length or portion is then cut off the bulk supply thereby forming an unhemmed or raw blank of the material. The blank is then processed, as for example by folding the cut edges or ends of the blank for forming a hem or finished edge. This is accomplished by hem folding a portion of the blank along its edge over on itself and sewing the folded edge in place thereby forming the finished edge.

The present invention embraces apparatus which may readily be employed as a sheet material edge folding component in the apparatus of the said copending application.

Some currently employed limp sheet material folding devices are complex, dynamic action devices which include multiple moving parts to actively fold the sheet material over on itself. The present limp sheet material folding device is essentially passive, the device advantageously directing or orienting the limp material edge into a natural flow-folded condition, while the limp material is continuously moving along a predetermined path.

Other currently employed limp sheet material folding devices, which are considered passive devices, essentially force or cramp the sheet material into a folded condition against the natural stress of the material. This cramping and/r forcing action is accomplished by using tight and/or sharp channels through which the sheet edge is forced. This type of folding operation of the prior art often results in warping or distorting and/or wrinkling the sheet material in the fold itself and often causes uneven ends sometimes referred to as ears." This prior art type of folder also is not self-starting inasmuch as the material is usually manually placed into position for starting purposes, and the action of the sewing machine thereafter pulls the rest of the material through the folder.

Among the advantages of the present limp sheet material folding device are those resulting from its ability to be selfstarting and its action in passively guiding or orienting the continuously moving limp sheet material into its natural contour or fold conformation so that, as opposed to forcing or cramping the material into a contorted, unnatural configuration to acquire a hem fold, the limp sheet material is guided or oriented into a condition whereby the sheet material itself overcomes its own natural stress or resistance to folding or bending and essentially folds itself.

As background information it is noted that apparatus or machinery embracing the principles set forth and described in the said copending application may be made so that the apparatus is capable of handling different sizes of sheet material, and/or make different sizes of finished flat articles. The different sizes of finished flat articles, such as different sizes of flat bed sheets (i.e. twin size, double size, queen size and king size, for example) may be different in width, different in length and may also require different size hams. ln order to convert from making twin bed size (twin size) sheets to double bed size (double size) sheets a change in the size (width) of the bulk material used is normally required so that the wider sheet blank is drawn off and severed. ln order to convert into a larger (longer) sheet an adjustment in the drawing apparatus may be made. The apparatus of the said copending application is presented as being capable of handling sheet material of different width, and longer blanks may be obtained by adjusting the sheet-drawing mechanism, thus, both wider and/or longer blanks may be made in the apparatus without a substitution of the components of the apparatus.

When a hem of different size than that previously made is required a substitution of components may be required. This may require removal and replacement of the hem-folding device. In order to substitute or replace the hem-folding device another folding device must be obtained, perhaps from a storage place. The currently used hem-folding device must be removed and the substitute hem-folding device must be installed in the proper position and the removed folding device stored for subsequent retrieval for later use.

Another aspect of the present invention provides for a onestep removal-replacement and retrieval-storage system in which selection of one folding device may be made from a plurality of prepositioned folding devices of different size. Convenient and compact storage of other hem-folding devices and convenient availability and retrieval from such storage is provided.

Such convenient, compact and readily available storage and retrieval may be descriptively described as a rotary indexable storage and retrieval system and in the present disclosure such rotary indexable system is shown in quadrant arrangement, although fewer or more sections in a rotary storage system may be had, and provided for, if desired.

It is therefore, an object of the present invention to provide a limp material folding device for progressively urging the edge and adjacent portion of continuously flowing limp sheet material into a condition whereby the material folds itself as such material passes through the folding device.

Another object is to provide an improved hem-folding device for progressively directing and orienting limp sheet material to progressively accurately advance over itself into a folded condition as the limp sheet material passes through such device without distorting and/or forcing the material into an unnatural contour.

A further object is to provide a hem-folding device which is self-starting in action when a continuously moving sheet of limp material is moved along a predetermined path into contact with the device.

Another object is to provide a rotary indexable storage and retrieval system for hem-folding devices which makes available convenient selective storage and retrieval in a one-step arrangement.

These and other objects will become apparent from reading the following detailed description with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a natural flow folding device positioned on a rotary indexable storage andretrieval unit, with portions of the rotary indexable storage unit shown diagrammatically inexploded position in a workline;

FIG. 2 is a plan view of one natural flow folding device on a section of a rotary indexable storage unit showing the action of a sheet of limp material passing through the folding device;

FIG. 3 is a front elevation view along line D-D of FIG. 2;

FlG. 4 is a plan view of another natural flow folding device of smaller size mounted on another section of a rotary indexable storage unit showing the action of a sheet of limp material passing through the folding device;

FIG. 5 is a front elevation view along the line E-E of FIG. 4;

FIG. 6 is an exploded view of a natural flow sheet material folding device positioned on a quadranted rotary indexable storage unit; and

FIGS. 7, 8 and 9 are sectional elevation views showing progressive action of the natural flow sheet material folding device of FIG. I, such views being taken respectively along the lines A-A, 8-8 and C-C.

Referring to FIG. 1 in more detail, a rotary indexable storage and retrieval system in quadranted arrangement, is shown with a natural flow folding device positioned on each of the four shoulders. The rotary indexable storage system is positioned so that one of its shoulders 14c aligns with the work carrying surface of the workline 15a, 15, 15b. The shoulder 14c serves as a mounting for one natural flow folding device. Parts of other natural flow folding devices may be seen as mounted on another shoulder 14b. FIG. 6 shows an exploded view of a natural flow folder, corresponding with the folding device seen positioned in the workline of FIG. 1.

The rotary indexable storage and retrieval unit rotates on an axis 10, and has an axle 11 mounted in bearing mounts 12 and 13. The four bases or shoulders 14, 14a, 14b and 14c extend radially from the hub around the axle 11, each shoulder supporting a natural flow folding device of a different size.

Each bearing 12 and 13 is supported by a mount 18 and 19, respectively, and a locking pin 17 provides a means oflocking the rotary indexable storage unit in a desired rotational position as selected by the user.

The inside, horizontal shoulder, seen as 14c in FIG. 1, essentially mates with and forms a part of the workline 15a, 15, 15b, along which a sheet of limp material is conveyed, such as a bed sheet, for example. Means for conveying the sheet 20 is represented by the belt and pulley wheel arrangement 22 shown partially broken away to clarify the illustration. One means for conveying a sheet of material along a workline is illustrated and claimed in my copending application, Ser. No. 699,910 filed Jan. 23, 1968, under the title Belt Conveyor Means With Pressure Distribution Means." It should be understood that the sheet material 20 is continuously moving along the workline 15b, 15 and 15a in the direction of arrow 21.

Referring also to FIG. 6 the natural flow folding device includes a fold stop and edge-orienting ramp 23/24 which is mounted on the shoulder 14c, as by welding, for example. A natural flow guide plate 25 is mounted on the fold stop 23 by nut 31 and bolt assembly in position so that the sweep or contour 25s of its leading end follows the natural bend of the sheet material in process of being folded, as the material continues its arcuate sweep or flow toward the body of the material, for the size of fold desired. The ply separator with retaining shoulder 26 is illustrated with a ski toe 26s. The ply separator plate 26 is held suspended over the shoulder or base 140 by a plurality of brackets 29 by adjustable attachment means which are represented as machine screws 32 coupled to the fold stop 23 and to the ply separator plate 26, thus supporting the ply separator plate 26 in the desired position.

As clearly seen in FIGS. 1 and 2 the sheet material 20 is conveyed along the workline so that its edge 20e extends over the edge-orienting ramp 24. The edge 20e proceeds up the ramp as the sheet 20 is progressively conveyed forward, and the inner portion or body of the sheet slips under the ski toe 26s. The rise of the ramp is such as to permit the sheet material to assume a natural bend at 20f(see FIG. 7) with the bent portion of the sheet snuggly positioned against the lateral face of the fold stop 23. The leaf 26L of the ply separator plate 26 passively urges the bend or fold 20f so that the bend 20f maintains its position against the fold stop 23.

After the sheet edge 20e has been lifted sufficiently in a vertical position the natural tendency of the material is to bend or fold when the natural stiffness of the fiber or material strength is overcome. This natural flow or natural fold contour or sweep is essentially the contour and sweep provided on the leading end portion of the natural flow guide plate 25 at 25s (see FIG. 8). The edge 20e of the sheet 20 follows its natural tendency to fold arcuately toward the body of the sheet material, and thus the edge 20e settles on the upper surface of the leaf 26L of the ply separator plate 26. Thus, a smooth folding of the sheet 20 is accomplished by passively urging the sheet material to follow its natural tendency to overcome its natural stiffness. This smooth fold may be seen in FIG. 9 with the sheet material snuggly folded with the fold 20]" against the fold stop 23 and the leaf 26L of the ply separator plate 26 passively urging the sheet to hold such position.

Referring particularly to FIG. 6, the plate 230 shown in part, represents the edge stop plate of the natural flow folding device positioned on the shoulder 14b.

Referring to FIG. 2, the natural flow folding device of FIG. I (mounted on the shoulder of the rotary indexable storage unit) is shown in plan view. The sheet material 20 is shown being conveyed in the direction indicated by the arrow 21. The relationship between the edge 20e and the edgeorienting ramp 24 may be seen. As the edge 20e rises up the ramp the bend at 20f is created by the sheet material itself. The sweep 25s of the natural flow guide plate 25 contours or follows the natural curve or flow of the sheet material which develops from the natural tendency of the sheet material to fold over itself after overcoming its natural stiffness (see FIG. 8 also). In FIG. 3 the folded sheet material may be seen as the sheet material exits from the natural flow folding device. Attention is directed to the size of the natural flow folding device with respect to the fold created by the sheet material.

The size of the components which make up the natural flow folding device depend upon the bend or fold characteristics of the sheet material to be folded and the size of the fold to be created.

Attention is directed to FIGS. 4 and 5. It is here assumed that the same material or some type of material is conveyed through the folder on the shoulder 14b, which is positioned in alignment with the work-carrying surface 15. However, from FIGS. 4 and 5 it will be noticed that the fold so created is substantially smaller than the fold created and shown in FIGS. 2 and 3. Essentially the natural flow folder shown in FIGS. 4 and 5 is a smaller scale model than the model illustrated in FIGS. 1, 2 and 3. It will be appreciated that for the same sheet material or for sheet material having the same fold or bend characteristics, the sweep and contour of the bend or fold along the edge depends upon the size of the hem fold created.

Thus I have shown and described a passive natural flow folding device and a rotary indexable storage and retrieval system. It will be appreciated that each base or shoulder of the rotary storage unit is a radial extension of the hub about the axle and more than four bases or shoulders or fewer than four shoulders may be used in a rotary indexable storage unit, if desired. In addition, the rapidity and ease with which one folding device may be substituted for another, that is, by rotating the rotary storage and retrieval unit, greatly reduces the downtime of any machine in which periodic change of a fold ing device is desired and/or necessary. Further, the folding devices normally used, as well as those shown and described herein, are heavy and/0r bulky, being difficult to handle. This new storage and retrieval system avoids the necessity of excess handling of the folding of the folding device during change of the device, one for another.

It will further be appreciated that the natural flow folding device is a passive device which is self-starting and guides and orients the actively passing (continuously moving) sheet material into a natural fold condition. From the foregoing it will be understood that the size and contour of the orienting and guiding components are arranged to conform with the characteristics of the sheet material to be folded and the size of the fold thereby passively created.

Thus I have shown and described my passive natural flow folding device and a rotary indexable storage and .retrieval system therefore. Some change and/or modification have been suggested. Other changes and/or modification as will be familiar to the skilled in the art may be made without departing from the spirit of the invention as defined in the appended claims.

I claim:

1. A device for passively urging a sheet of limp material to fold its edge over itself in a natural flow including:

means for conveying said sheet of limp material along a workline with the edge of said material to be folded in predetermined relation to said workline;

said workline including said device positioned to intercept the edge and adjacent portion of said sheet of limp material;

a ramp for elevating said edge and adjacent portion thereof;

means for restraining the body portion of said sheet while permitting the said edge and adjacent portion to elevate along said ramp for forming a bend in said adjacent portion and for urging said edge and adjacent portion into a substantially standing position;

a fold flow guide for urging continuance of said bend in the same direction, the contour of said flow guide substantially paralleling the natural flow fold of said material;

ply-separating means for separating the folded adjacent portion from the said body over which the folded portion lies; and

means for urging the bend against a fold stop for positioning said bend.

2. A device for passively urging a sheet of limp material to fold its edge over itself in a natural flow as claimed in claim 1, in which:

said device is mounted upon a shoulder of a rotatable unit which is rotatable about an axis extending parallel with said workline and being offset from said workline; and

in which another similar device for passively urging a sheet of limp material to fold its edge over itself in a natural flow is mounted upon another shoulder of the rotatable unit for enabling the respective devices to be substituted one for another by rotating said rotatable unit about its axis into different operative positions.

3. A device for passively urging a sheet of limp material to fold its edge over itself in a natural flow as claimed in claim 1, in which:

said ply-separatingmeans is an elongated plate extending in the direction of said workline; and

said elongated plate has a ski toe for enabling the body portion of said sheet of limp material to slide under said ply separating means.

4. Apparatus for storing a plurality of limp material folding devices for providing a one-step storage and retrieval system and for selectively presenting such folding devices singularly as part ofa workline including:

an axle mounted for rotating about an axis;

said axis being substantially related to the workline;

at least two bases coupled to and extending radially from said axle, each receivable in said workline;

means in said workline for receiving one base at a time as said axle is selectively positioned rotatably about said axis;

one of said bases having a first folding device for folding a first size fold in said limp material when positioned in said workline;

said second base of said at least two bases having a second folding device for folding a second size fold in said limp material when positioned in said workline;

said bases extending radially from said axle from a different radial position;

one of said folding devices having a ramp for elevating the edge and adjacent portion of limp material passed along said workline; means for restraining the body portion of said limp material while permitting said edge to elevate along said ramp for forming a bend in said adjacent portion created from the said edge arcuately moving toward the said body of said material while said body is restrained, thereby urging said edge into a substantively standing position; I

a natural fold guide for urging continuation of the arcuate movement of said edge, in the same directions, the contour of said guide substantially paralleling the natural flow fold of said material ply-separating means for separating the folded edge from said body over which said folded portion lies; and means for urging the bend against a fold stop for positioning said bend. 

